The Serteng Formation outcrops in the south part of the East Kunlun consisting mainly of metaclastic rocks, which experienced the regional metamorphism and contact metamorphism. From the bottom up, the sedimentary facies of the Serteng Formation are deepwater turbidite, shallow water sediment, and coastal-shallow water sedimentary, which constitute a regressive sequence. The sedimentary characteristics of the Serteng Formation indicate that it was formed during the closure of the Proto-Tethys. The ever existing controversy about the formation time of the Serteng Formation is primarily due to the absence of fossil. We expect to provide some valuable information about the provenance and stratigraphic formation time of the Serteng Formation through detrital zircon U-Pb dating. We have obtained five age ranges, such as>2500 Ma, 2300~2600 Ma, 1600~1800 Ma, 800~1200 Ma, and 421~600 Ma. The existence of zircon grains with ages older than 2500 Ma may indicate the existence of ancient crystalline basement in the East Kunlun. The rest age ranges indicate the source regions of the Serteng Formation have experienced complex multi-phase geological events, which corresponding to the Early Paleoproterozoic, Late Paleoproterozoic, Late Mesoproterozoic, Early Neoproterozoic and Early Paleozoic tectono-magmatic events, respectively. The paleocurrent direction abstracted from cross bedding indicates the clastics in the Serteng Formation are mainly from the north adjacent regions. Comparing the detrital zircon ages from the Serteng Formation with the adjacent stratigraphic units, we conclude that the Baishahe Group, Xiaomiao Group, Wanbaogou Group, granite formed during early Neoproterozoic tectono-magmatic event, and the evolution of the Proto-Tethys are the mainly provenance of the Serteng Formation. Combining the youngest zircon age 421±7 Ma and the age of rocks which intrude the Serteng Formation, we narrow the formation time of the Serteng Formation to 421~413 Ma. Furthermore, the Serteng Formation recorded the subduction to closure history of the Proto-Tethys in the East Kunlun, so we can use the stratigraphic formation to constraint the closure time of the Proto-Tethys in the East Kunlun.%出露于东昆仑地区的赛什腾组是一套变碎屑岩,底部为具鲍马序列的深海浊流沉积,往上总体为下细上粗的浅海–滨浅海沉积,构成一套海退沉积序列,是东昆仑地区原特提斯洋闭合过程中形成的物质记录。由于赛什腾组中缺少化石记录,前人对其地层时代的归属一直存在争议。本文通过对赛什腾组碎屑锆石年龄谱的研究,恢复了物源区经历的几期重大构造–岩浆事件,对其物质来源及沉积时代进行了约束,为构建东昆仑及其邻区的构造演化历史提供了参考。研究得到赛什腾组碎屑锆石年龄谱存在>2500 Ma、2300~2600 Ma、1600~1800 Ma、800~1200 Ma和421~600 Ma五个年龄区间,相应指示其最终物源区可能存在古老结晶基底，并先后经历了早元古代早期构造–岩浆事件、早元古代晚期构造–岩浆事件、中元古代晚期构造–岩浆事件(格林威尔运动)、新元古代早期构造–岩浆事件和早古生代构造–岩浆事件(原特提斯洋演化阶段)；将赛什腾组碎屑锆石年龄与恢复得到的古水流方向相结合，推测北部邻区的白沙河岩组、小庙群、万宝沟群和新元古代早期构造–岩浆活动及原特提斯洋演化后期在东昆仑地区形成的大量中酸性岩浆岩是其主要物源；根据得到的年龄为421±7 Ma的最年轻碎屑锆石,结合侵入其中的年龄为413.8±0.8 Ma的二长花岗岩,将赛什腾组的沉积时代限定于421~413 Ma,结束了前人对其形成时代的争议；并进一步根据赛什腾组是东昆仑地区原特提斯洋发生俯冲消减直至碰撞闭合的填满沉积序列,提出赛什腾组的地层沉积时代可认为是东昆仑地区局部原特提斯洋发生闭合的最大年龄。
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